drm/virtio: implement context init: probe for feature

Let's probe for VIRTIO_GPU_F_CONTEXT_INIT.

Create a new DRM_INFO(..) line since the current one is getting
too long.
Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-5-gurchetansingh@chromium.orgSigned-off-by: Gerd Hoffmann <kraxel@redhat.com>

drivers/gpu/drm/virtio/virtgpu_debugfs.c

@@ -52,6 +52,7 @@ static int virtio_gpu_features(struct seq_file *m, void *data)
 			    vgdev->has_resource_assign_uuid);
 
 	virtio_gpu_add_bool(m, "blob resources", vgdev->has_resource_blob);
+	virtio_gpu_add_bool(m, "context init", vgdev->has_context_init);
 	virtio_gpu_add_int(m, "cap sets", vgdev->num_capsets);
 	virtio_gpu_add_int(m, "scanouts", vgdev->num_scanouts);
 	if (vgdev->host_visible_region.len) {

drivers/gpu/drm/virtio/virtgpu_drv.c

@@ -172,6 +172,7 @@ static unsigned int features[] = {
 	VIRTIO_GPU_F_EDID,
 	VIRTIO_GPU_F_RESOURCE_UUID,
 	VIRTIO_GPU_F_RESOURCE_BLOB,
+	VIRTIO_GPU_F_CONTEXT_INIT,
 };
 static struct virtio_driver virtio_gpu_driver = {
 	.feature_table = features,

drivers/gpu/drm/virtio/virtgpu_drv.h

@@ -236,6 +236,7 @@ struct virtio_gpu_device {
 	bool has_resource_assign_uuid;
 	bool has_resource_blob;
 	bool has_host_visible;
+	bool has_context_init;
 	struct virtio_shm_region host_visible_region;
 	struct drm_mm host_visible_mm;
 

drivers/gpu/drm/virtio/virtgpu_kms.c

@@ -191,13 +191,19 @@ int virtio_gpu_init(struct drm_device *dev)
 			    (unsigned long)vgdev->host_visible_region.addr,
 			    (unsigned long)vgdev->host_visible_region.len);
 	}
+	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_CONTEXT_INIT)) {
+		vgdev->has_context_init = true;
+	}
 
-	DRM_INFO("features: %cvirgl %cedid %cresource_blob %chost_visible\n",
+	DRM_INFO("features: %cvirgl %cedid %cresource_blob %chost_visible",
 		 vgdev->has_virgl_3d    ? '+' : '-',
 		 vgdev->has_edid        ? '+' : '-',
 		 vgdev->has_resource_blob ? '+' : '-',
 		 vgdev->has_host_visible ? '+' : '-');
 
+	DRM_INFO("features: %ccontext_init\n",
+		 vgdev->has_context_init ? '+' : '-');
+
 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
 	if (ret) {
 		DRM_ERROR("failed to find virt queues\n");